CO2 Laser-MIG Arc Hybrid Welding of Aluminum Alloy 6061

• Main Authors: Yuan-feng Chang, 張源峰
• Other Authors: Yih-fong Tzeng
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/70673189222840999376

碩士 === 國立高雄第一科技大學 === 機械與自動化工程所 === 93 === The combination of laser and MIG arc is internationally becoming a potentially useful technique after being researched for years abroad. The hybrid welding process has been demonstrated to offer the advantages of enabling to increase depth penetration ratio, welding speed, and decrease the susceptibility of hot cracking etc. However, this technique is still in its infancy in the domestic industrial applications. If the hybrid welding was successfully developed, it is expected to reduce the post-processing cost, enhance the weldmental quality, and eventually the competitiveness if introduced to Taiwan manufacturing-related industries. In this paper, the welding of 6061 aluminum alloy was carried out using the combined sources of the CO2 laser beam and the MIG arc. Due to that the CO2 laser-MIG arc hybrid welding has been operated using the trial-and-error method, and the process was essentially not unreliable. Therefore, this research aims to not only develop the technology of CO2 Laser-MIG arc hybrid welding of aluminum alloy 6061-T6, but also to optimize multiple performance characteristics of hybrid welding using Taguchi methods coupled with principal component analysis (PCA). The multiple characteristics investigated include tensile strength, bending strength, and micro-hardness etc. According to experimental results, the optimal process conditions for the hybrid welding process can be determined as A2 (filler material: aluminum alloy 5356), B3 (laser power: 1450W), C3 (MIG current: 155A), D2 (welding speed: 550mm/min), E3 (gap size: 0.3mm), F1 (laser assist gas flow: 30kg/cm2), G2 (MIG assist gas flow: 26kg/cm2), and H1 (wire extension length: 12mm), which improve tensile strength, elongation ratio, porosity ratio, and bending strength for the weldments quality. In addition, the analysis of variance (ANOVA) shows that the test is highly reliable in the hybrid welding experiment due to error 4.0068%.